Main and branch both 200amp breakers

Just did a 1 year Inspection in Hutto ,Tx and both the service panel outside and branch panel in the garage had 200 amp main breakers.
Outside was fine but, the branch service has 100 amp /conductors for each of the live, and ground and with a 200 amp main breaker in the box. I wrote it up as a safety deficiency. It was over fused. I conferred with a senior inspector friend of mine who also agreed with me.
Any thoughts?

I do not understand what you mean by "the branch service has 100 amp /conductors for each of the live and ground.

“service panel outside and branch panel in the garage”

You have 2 service panels. Each panel has a main disconnect. Each main disconnect breaker is rated at 200 Amp.

Take your time and explain this to me. What you mean by "the branch service has 100 amp /conductors for each of the live and ground."

The 200 amp main in the garage panel is fine as it is only serving as a disconnect. You’ve correctly stated that the 100 amp conductors are not being protected because they are connected on the load side of the 200 OCPD at the service. Just out of curiosity what size conductors did they use for the 100 amp feeder? Did you snap any photos of the two panels?

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My apologies for any confusion here!
Robert M, here is a photo of branch service panel in Garage. 2 g AL conductors which are 100amps. See guage. My concern was a 200 amp breaker/main shut off. May not be a big deal, but if for some unknown reason, power surge, lighting etc, happens it appears to me there should have been a 100 amp breaker/main shutoff instead. Thanks for feedback.

It says right on the breaker wire size 2
your gauge shows its the correct size.

If the breaker at the service panel is also 200 then you are correct in calling it out like Robert said. Those should be 4/0 aluminum.

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They split up lighting branch circuits in a panel and system branch circuits in a panel? Each protected by 200 main breaker?

This is what has me scratching my head. Since I only see 120-V circuits in the panel are the 240s in the other? And is there a chance this panel is being fed from a 100 amp breaker in the other panel? I have seen this done where someone just took an off the shelf panel with a 200 amp breaker already installed and used it for a secondary distribution panel with a 100 amp disconnect in the main, but it still bugs me because I think I just see a three conductor wire coming into the panel. Either way it looks like you found a major problem.

The main service panel has the same shut off breaker as the panel in the garage. See attached photo of main panel. Fyi, the meter is to the left with service conductors entering through the bottom left of the main panel… The conductors that feed the 2nd panel in the garage (to lower Right of busbar), do each have a 100amp breaker in the main. So that to me makes the garage panel protected. In addition the main panel serves two 40 amp breakers to the range and dryer along with a 30 amp breaker for the HVAC system. In further research I find that the secondary panel in the garage is not required to even have a main shut off switch, let alone a breaker/shut off switch. It just makes it easier to shut off all the branch circuits in the home without having to go outside to the main. At the time of my inspection I was leaning on the side of caution for my client. So in my current opinion I now believe this set up is ok and not a safety issue. I believe I should now call my client to explain my update and then send them an updated report. I don’t want them to bring out an electricion for no real issue… Do you all agree that is what I should do?

Got you. Feeders have 100 ampacity if the AWG is correct. Sorry, David.
Robert M picked up on that.

All in all, an electrician can downsize the garage main disconnect to 100 amp main disconnect. They are lighting circuits. I think the max OCPD is 25A

As long as that 100 amp feeder has 4 conductors, and the neutrals are separated in the garage panel, there is no issue.

#2 aluminum is only rated for 90 amps.


You can’t have 2 service panels, or 2 main disconnects. That language will confuse everyone. Either it’s the service or it’s a distribution.

Morning, Daniel.
Hope you are well.

I concur with one of your points. I was just replying to the OP’s statement; “both the service panel outside”

You can have up to 6 disconnects.

You are correct (bold part) when this is an attached garage. There are some other issues however. As mentioned earlier the #2 Al feeder cannot be protected at 100 amps because at 75° C its ampacity is 90 amps not 100. 90 amps is a standard size so a 100 amp OCPD cannot be used to protect the feeder.

Also in the service panel there is no visible grounding electrode conductor (GEC) connected to the neutral. It does appear that there are large bare copper conductor that could be a GEC but it is apparently attached to the EGC bus which is a violation, it must connect to the neutral bus when the main bonding jumper (MBJ) is a screw.

Picture not showing all in much detail or hiding some connections. GEC (AL) is routed back into main via a Ufer grounding connection and comes in through bottom right of box then wraps to left and up to top of bus. Cu wire is also attached to that same bus and wraps down and to right to the EGC bus. Neutral is bonded to panel top right.

The larger aluminum stranded conductor looks like it’s within the cable for the garage feeder which makes it an EGC not the GEC.

Nope to Ufer which goes between brick veneer and down to garage. I did not take a picture of it, but it was the same AL cable. Thanks

So where is the aluminum EGC for the feeder cable?